As a radio communication device, a PC card that has an antenna built-in inside a casing, and that is used inserted into an expansion slot of a personal computer or the like, has been put to practical use. This built-in antenna type PC card has been developed with the object of further miniaturizing PC cards furnished with movable external antennas. This PC card achieves miniaturization by mounting a built-in antenna within a casing instead of providing an external antenna outside of the casing. As technology related to the PC card with built-in antenna, Patent document 1 below discloses a compact antenna (reverse-F antenna), and a PC card with this compact antenna built-in, that can receive a desired vertical polarization component, and can widen the frequency bandwidth of VSWR, even when built-into a PC card or the like of uniform thickness.
The compact antenna is constituted by a substrate and chip parts made of resin that are mounted on the substrate. The substrate includes ground conductors formed on the back of the substrate, a first short-circuit conductor wiring formed on a main surface of the substrate, and a through-hole that connects these. The chip parts include a second short-circuit conductor wiring, a radiating conductor, a short-circuit conductor, and a power supply conductor wiring. The second short-circuit conductor wiring is formed on the underside of the chip parts and faces the first short-circuit conductor wiring on the substrate. The radiating conductor is formed on the upper surface of the chip parts. The short-circuit conductor is formed on the end surface of the chip parts, and connects the second short-circuit conductor wiring and the radiating conductor. The power supply conductor wiring is formed on the side surface of the chip parts and is connected to the radiating conductor.
[Patent Document 1] Japanese Unexamined Patent Application, First Publication No. 2003-133847